Electrical connector



Jan. 4, 1966 J. s. ZDANIS ELECTRICAL CONNECTOR Filed Dec. 20, 1962 Fla. 2

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lmlium IIRI'IIIHKIIIIIII Illll IIIIIIIIIIHIII l/vve/vToa JOHN S. ZDAN/5 By ATTORNEYS United States Patent Ofi ice 3,227,991 Patented Jan. 4, 1966 3,227,991 ELECTRICAL CONNECTOR John S. Zdanis, Watertown, Cnn., assignor to The Siemon Company Filed Dec. 20, 1962, Ser. No. 246,272 2 Claims. (Cl. 33998) This invention relates to a new and improved type of electrical connector and more particularly, to an electrical connector for low voltage insulated wires.

One of the most common means for effecting an electrical connection in industry is by means of soldering or welding two or more electrical conductors together. However, there are many instances in which these connections are not desirable since, to unconnect the conductors, it is necessary to loosen and break the soldered connection such as by the application of heat. Therefore, when it is necessary to etfect new connections frequently and break old connections, such as on terminal connecting blocks in telephone distribution cabinets, the common soldered or brazed connections are unsatisfactory. For example, in cabinets of this type Where it is necessary to allow ready connection of new subscribers and the disconnection of subscribers whose service is terminated, solderless connections are preferable.

Solderless connections depend on pressure or stress exerted by the connecting apparatus on the conductors to insure intimate electrical contact and to hold the conductors in place. Many types of solderless connections are known such as sockets or plugs wherein a male element is inserted into a female element. One common type of solderless connection, often used in terminal connecting blocks such as are used by the telephone industry, is the screw connection. Such a terminal connecting block may comprise a base of insulating material in which there are embedded a plurality of threaded terminals or posts, each post being provided with a nut. The terminals between a conductor coming from the exchange and a conductor or conductors going to the individual subscribers may be made on a single post by wrapping the conductors around the post and then tightening the nut. On the other hand, the terminals in one of the parallel rows may be connected to the incoming conductor from the exchange and the terminals in the other row may be connected to the conductors going to the subscribers. Connections between the two rows of terminals may be made, for example, by means of bridging wires. To use this type of terminal connecting block, it is necessary to strip the insulation from the ends of the conductors, wrap them around the post and then tighten the nut to insure good contact and to hold the conductors in place. This type of electrical connector is subject to several disadvantages. In addition to the fact that the insulation must be manually stripped from the end of the conductor before it is connected to a terminal, it has been found that the pressure of the nut pressing down on the stud which is resisted by the upward thrust of the stud, results in metal fatigue, especially in the threads of the stud; and, after a period of time, results in a poor contact with the connector. Moreover, only a limited number of connections can be made effectively at any one terminal post. Furthermore, when the connecting block is subjected to sustained periods of vibration, the nuts have a tendency to become loose and contact with the conductors may be lost. Furthermore, when the nut is loose, the connection may be electrically noisy.

Other types of solderless connectors are subject to similar and equally objectionable disadvantages, i.e., it is generally necessary to strip the insulation from the conductor manually before making the connection. Moreover, such connections are often difficult to make; and, the connection, once made, may be adversely affected by vibrations and variations in temperatures.

It is an object of this invention to provide an electrical connector which automatically strips or ruptures the insulation from an electrical conductor in the use thereof in making a connection. It is another object of this invention to provide an electrical connector which will maintain good electrical contact indefinitely. It is a further object of this invention to provide a device by which electrical connections may easily and simply be made. Still another object of this invention is to provide a terminal connecting block which will permit a number of connections to be made on one terminal in a much more compact space than has previously been possible.

Briefly, the objects of this invention are attained by providing an electrical connector which comprises two spaced apart fingers which are located in the parallel planes. Preferably, although not necessarily, these fingers are parallel to one another. A tooth member is obliquely disposed with respect to the two spaced apart fingers and is positioned in a plane lying between these two fingers. The upper portion of the tooth member is inclined away from the two fingers and a lower portion of the tooth member is adjacent to the fingers. The opposing surfaces of the fingers and the tooth member have edge portions which serve to rupture the insulation or insulated conductors which are forced therebetween.

A preferred embodiment of this invention is illustrated in the accompanying drawings wherein:

FIG. 1 is a side elevational view of a connector constructed in accordance with this invention.

FIG. 2 is an end elevational view of the connector shown in FIG. 1.

FIG. 3 is a top plan view-of the connector shown in FIG. 1.

FIG. 4 is an enlarged sectional view of a portion of the connector shown in FIG. 1, showing the insulation stripped from the electrical conductor which is in electrical connection with the connector.

FIG. 5 is a perspective view of a portion of the connector shown in FIG. 1.

The drawings are more fully explained hereinafter with particular reference to the various numerical designations, each individual numeral having the same significance in the dilferent figures.

Referring more specifically to the drawings, there is shown an electrical connector 10 comprising two rows of fingers, 11 and 12. The row of fingers 11 is spaced apart from the row of fingers 12. Each of the rows of fingers 11 and 12 com-prises a plurality of vertical fingers 11a and 12a. Each finger in each row is spaced apart from the next adjacent finger in the same row. The fingers 11a in one row are in substantial alignment with the fingers 12a in the other row, thus forming a plurality of pairs of spaced apart fingers 11a-12a. The fingers 11a and 12a preferably contain serrations 13 on one edge thereof.

Positioned between the two rows of fingers 11 and 12 is a row of obliquely disposed, resilient teeth members 14. One side of each of the teeth members 14 is preferably situated between an aligned pair of fingers Ila-12a. The other side of each of the teeth members 14, which preferably contains a plurality of serrations 15, is obliquely disposed with respect to the next adjacent pair of spaced apart fingers Ila-12a so that the upper portion of the serrated side of each of the teeth 14 is inclined away from the serrated edges of the next adjacent pair of spaced apart fingers Ila-12a and a lower portion of the serrated side of each of the teeth 14 is adjacent or in proximity to the serrated edges of the next adjacent pair of spaced apart fingers Ila-12a.

The rows of fingers, 11a and 12a, and the row of teeth members 14 may be formed of any suitable conducting material such as an alloy of Phosphor bronze, berrylliurncopper, etc. The rows of fingers, 11 and 12, and the row of teeth members may be formed by stamping them from a strip of metal. The plates so formed may then be assemble-d and held together adjacent to each other and in contacting face-to-face relationship in spaced apart planes by means of rivets 16.

There is thus provided a plurality of V-shaped grooves or slots, bounded on the one side by the serrated edge of a tooth member 14 and on the other side by the serrated edges of a pair of spaced apart fingers Ila-12a. The serrations are directed generally inwardly toward the apex of the V-shaped slot. Connection of a low-voltage insulated electrical conductor 17 to the connector 10 may be quickly and easily accomplished by forcing the condoctor 17 downwardly in one of the grooves or slots. The opposing surfaces of the tooth members 1 4 and the adjacent pair of spaced apart fingers 11a-12a rupture the insulation 18 on the conductor 17 and electrical contact is thus established between the connector 10 and the conductor wire 19. Since the insulation 18 on the insulated conductor 17 is pierced only at the point of contact with the opposing edges of the tooth member 14 and the adjacent pair of spaced apart fingers Ila-12a, there are no large areas of bare conductor wire 19 exposed or showing. The serrations on these opposing edges provide a powerful gripping action on the conductor, thereby rendering the connection unaffected by long periods of extensive vibrations. Moreover, the spatial relationship of each of the teeth members 14 with respect to the next adjacent pair of spaced apart fingers Ila-12a (i.e., the tooth member being positioned in a plane lying between the pair of fingers) results in a much more secure connection than would otherwise be possible. Furthermore, the fact that one side of each of the teeth members 14 is situated between an aligned pair of fingers Ila-12a provides a structure which is extremely resistant to deformation and bending.

Many variations and related embodiments other than those described above will be apparent to those skilled in 4 the art. These novel connectors may be used, for example, in association with a terminal connecting block in which case the bottom portion of the connector 10 is embedded in a base member of an electrical insulating material.

I claim:

1. An electrical connector comprising:

three parallel plates in spaced apart planes,

a plurality of finger members coplanar with and located on the outermost said plates and disposed with finger members in one row in alignment with finger members in the other row, thereby forming a plurality of pairs of spaced apart parallel finger members,

a plurality of tooth members coplanar with and on the innermost said plate and disposed obliquely to said fingers, each of said tooth members having insulation rupturing edge portions spaced from one pair of said finger members at its outermost end and inclining inwardly to be in proximity to a same one pair of finger members to define a generally V-shaped slot, and a plurality of serrations facing said V- shaped slot locate-d on at least one of said members, said serrations pointing generally inwardly toward the apex of said V-shaped slot; whereby an insulated conductor will have its insulation severed when it is inserted between a tooth and a pair of fingers.

2. An electrical connector according to claim 1 wherein said plates are in contacting face-to-face relationship.

References Cited by the Examiner UNITED STATES PATENTS 1,956,019 4/1934 Gilbert 339-97 2,501,187 3/1950 Oortgijsen 33995 2,694,189 11/1954 Winsching 339-97 3,112,147 11/1963 Pferd et al. 33997 FOREIGN PATENTS 728,064 4/ 1955 Great Britain.

JOSEPH D. SEERS, Primary Examiner. 

1. AN ELECTRICAL CONNECTOR COMPRISING: THREE PARALLEL PLATES IN SPACED APART PLANES, A PLURALITY OF FINGER MEMBERS COPLANAR WITH AND LOCATED ON THE OUTERMOST SAID PLATES AND DISPOSED WITH FINGER MEMBERS IN ONE ROW IN ALIGNMENT WITH FINGER MEMBERS IN THE OTHER ROW, THEREBY FORMING A PLURALITY OF PAIRS OF SPACED APART PARALLEL FINGER MEMBERS, A PLURALITY OF TOOTH MEMBERS COPLANAR WITH AND ON THE INNERMOST SAID PLATE AND DISPOSED OBLIQUELY TO SAID FINGERS, EACH OF SAID TOOTH MEMBERS HAVING INSULATION RUPTING EDGE PORTION SPACED FROM ONE PAIR OF SAID FINGER MEMBERS AT ITS OUTERMOST END AND INCLINING INWARDLY TO BE IN PROXIMITY TO A SAME ONE PAIR OF FINGER MEMBERS TO DEFINE A GENERALLY V-SHAPED SLOT, AND A PLURALITY OF SERRATIONS FACING SAID VSHAPED SLOT LOCATED ON AT LEAST ONE OF SAID MEMBERS, SAID SERRATIONS POINTING GENERALLY INWARDLY TOWARD THE APEX OF SAID V-SHAPED SLOT; WHEREBY AN INSULATED CONDUCTOR WILL HAVE ITS INSULATION SERVED WHEN IT IS INSERTED BETWEEN A TOOTH AND A PAIR OF FINGERS. 